Combined chalk-line box and plumb bob



March 18, 1952 LANDON ET AL 2;589, 500

COMBINED CHALK LINE BOX AND PLUMB BOB V Filed sept. 19, 1949 Willi/I'll]I KIIIIIIIIIIIIIII M 1L am 010 5% Patented Mar. 18, 1 952 UNITED STATESPATENT OFFICE COMBINED CHALK-LINE BOX AND PLUlWB BOB ApplicationSeptember 19, 1949, Serial No. 116,488

1 Claim. 1

This invention relates to a combinedchalk-line box and plumb-bob and hasas an object the provision of a dual-purpose hand-tool for carpenters,masons and other artisans, of improved design and efficiency.

It is a further object of the invention to provide a dual-purpose toolof the character stated in which the constructional elements such as thebox or case necessary for service in one purpose are so made to servethe other purpose that the tool appears to be specifically designed forthe particular duty to which it may momentarily be applied.

Our invention possesses other advantages and more detailed objects whichwill be pointed out as the following description of a preferredembodiment of the invention proceeds, or will be apparent fromconsideration of the accompanying drawing, in which: s

Figure l is a plan view of a chalk-line box and plumb-bob embodying theprinciples of our in-' vention;

Figure 2 is a side view taken from the left of Figure 1;

Figure 3 is a longitudinal sectional view taken on the plane of sectionindicated by the line 3 3 of Figure 1;

Figure 4 is an interior view of the box or deeper portion of the case ofthe tool; and

Figure 5 is an interior view of the lid or shallower portion of thecase.

Having reference now to the details of the drawing, we have provided acase 1 comprising a box or deeper portion 8 and a lid or shallowerportion 9, both of which are adapted to be diecast from metal, plasticor other suitable material. The case I is characterized by its pyriformshape in its wider aspect, as seen in Figure 1, though differing from atrue pear in that the wider end of the case is not rounded or concavebut is formed with a point [0. The narrower end ll of the case 1 iselongated but blunt. As best illustrated in Figures 4 and 5, both thebox 8 and lid 9 are so shaped-that a circle may be inscribed in themcentered at the intersection of their major and minor diameters, thatis, the long diameter from the point It] to the blunt end II and thetransverse diameter of greatest length, and from this circle theperimeters of the case extend tangentially to the point H) at an angleapproximating 90 degrees and to the blunt end I I at a more acute angle.

In the transverse aspect, as viewed in Figures 2 and 3, the case 1 isrelatively thin, the lid 9 and the opposed side I! of the box 8 beingsubsuitable grip such as a ring 38.

end 39 of the cord 31 may be led through a suit-' 2 stantially fiatexteriorly. The lid 9 has a shallow flange I3 which fits within the box8 to locate the lid thereon, and a peripheral shoulder [4 which .engagesthe rim l5 of the box and. makes a smooth joint therewith.

The lid 9 is provided with a boss [1 on its interior side substantiallyat the intersection of its major and minor diameters and with a boss [8at the pointed end ID. The box 8 is likewise provided with an interiorboss I9, disposed on its major diameter at a little more than half thelength of the minor diameter from the intersection of the major andminor'diameters and towards the blunt end II. and I9 are bored andtapped, to be engageable by screws 23 and 2| which extend respectivelythrough holes 22 and 23 in the box and in the lid. When the screws 20and 2| are drawn tight an effective seal is established between theshoulder 14 and the rim l5. I

At the blunt end ll of the case, the flange I3 of the lid 9 isheightened to provide an end wall 25, which follows the curvature of theend II, and a transverse wall 23 joins the ends of the wall 25 to formtherewith a walled enclosure 21 which contains a felt pad 28. Similarly,the box 8 has curved wall 29 within its blunt end and a transverse wall30 forming therewith an enclosure 3| for a felt pad 32. The walls of theenclosures 21 and 3| do not meet when the lid 9 is tightened upon thebox 8, but the pads 28 and 32 extend beyond their surrounding walls soas to be compressed against each otherby the closure of the case. Asmall orifice 3,3 in the blunt end of the box 8 is aligned with themajor diam-Q eter .of the box and communicates with the interior of thebox at the interfacial level of the the pads 28 and 32 and outwardlythrough the orifice 33, the free end being provided with a The fastenedable hole (not shown) to the interior of the hub 35 and there to beknotted.

To prevent undue friction between the disks 36 and the adjacent lid andbox surfaces and to strengthen the lid and box to prevent distortionBoth the bosses l8 or denting, rings 48 are provided on the innersurfaces of the lid and box concentric with the boss I1. The rings 40hold the spool 34 spaced from the case and serve as end bearings for thespool. Additional larger rings 4| may be provided in virtual circularextension of the curved walls of the box and lid, thereby furtherstrengthening the case against distortion. The rings 4|, being at orjust beyond the periphery of the disks 36 also serve to prevent the cord31 from jumping the disks and being caught between the disks and thecase walls.

The hub 35 has an end extension 43 adapted to extend outwardly throughan opening '44 in the box bottom l2. A packing ring 45 may be providedto seal the opening 44 around the extension 43. The outer end of theextension 43 pivotally supports, as at 46, a crank 41 by which the spool34 may be rotated to wind the cord 31. The crank 41 is pivoted to beswingable in planes perpendicular to the box bottom l2 and is pro videdwith a handle 48 which at one end of the pivotal arcs is turnedoutwardly from the box bottom and at the other end of the arcs is turnedinwardly theretowards. The boss I9 is provided with a well or recess 49closed at its inner end and opening outwardly through the box bottom 12,and the crank 47 is of suitable length to permit the handle 48 to enterthe well 49 when turned theretowards.

It will be understood that the interior of the case "I normally containschalk or a like substance, which is sealed therein by the pads 28 and32, the packing ring 45, and the heads of the screws 20 and 2| whichclose all the openings leading to the interior of the case. Whether thetool is to 'be used as a chalk-line box or as a plumb-bob, the spool 34may be freed for rotation by swinging the crank 41 so that the handle 48is outwardly beyond the plane of the box bottom' I2. A desired length ofthe cord 3'! may then be pulled from the orifice 33. No brake isrequired to prevent an excess of cord being pulled out, other than thefriction of the pads 28 and 32 upon the cord. However, a positive lookupon rotation of the spool 34 is provided by engagement of the handle 48in the well 49. Two additional locking positions are also provided byenga gement of the handle 48 with the side walls of the case. Forexample, if unwinding the cord 31 produces a counter-clockwise motion ofthe crank 47, as seen in Figure 1, the rotation of the crank will bestopped at the points 50 and 5|, where the orbit of the handle 48crosses the side walls of the case, if the crank is swung pivotally toits locking inclination. Thus the length of the cord pulled from thecase can be regulated to less than one-half of a turn of the cord uponthe spool 34. Such exact regulation is often desirable when the tool issuspended as a plumbbob from a fixed support and it is desired to bringthe point l0 to approximate contact with a point to be marked.

' Thepyriform shape of the tool has physical advantages in addition toits attractive appearance. When the tool is used as a plumb-bob, the

mass at the lower end will cause the tool to hang in true verticalityfrom the cord emerging from the axially located orifice 33. The balanceof the plumb-bob may be made very exact by placing the handle '48 in theWell 49 so that the crank 41 is aligned with the vertical axis. Whencord is being drawn from the spool or wound thereon, it is natural toplace the wide portion of the tool in the palm of one hand with thefingers gripping the elongated end, the ring 38 or handle 48 being thenmanipulated with the other hand. Under these conditions the tool Wedgesitself into the gripping hand and is more easily and firmly grasped thana cylindrical or rectilinear tool.

Obviously, our invention is subject to modifications which fall withinits spirit and scope, we therefore do not wish to be limited to theexact embodiment herein described and illustrated, but to the scope andspirit of the invention as set forth in the appended claim.

We claim:

A chalk-line box having two opposed sides of generally pyriform outline,and connecting sides curved to follow said outline and perpendicular tosaid pyriform sides so as to form a box having a wide generally circularportion tapering gradually to an elongated but blunt end and taperingsharply to an opposite end, the blunt end of said box having an orifice;a spool mounted within said box, the axis of said spool beingsubstantially at the center of said circular portion; a cord wound onsaid spool and emerging from said orifice; a well in one of saidpyriform sides; and a crank for rotating said spool hingedly connectedto said spool for arcuate movement in planes perpendicular to saidpyriform sides and having a handle extending outwardly from said boxwhen said crank is at one end of said arcuate movement, and inwardlytoward said box at the other end of said movement, said crank having alength sufficient to permit said handle to rotate in a circle whichencompasses said circular portion of said box and is intersected by saidconnecting sides towards both ends of said box, said well being disposedon said circle and adapted to receive said handle.

ROBERT K. LANDON. JOHN R. THOMSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 873,686 Sharp Dec. 10, 1907932,218 Wilson Aug. 24, 1909 1,124,595 Dailey Jan. 12, 1915 1,876,473Spaeth Sept. 6, 1932 2,497,471 Shillman -Q. Feb. 14, 1950 FOREIGNPATENTS Number Country Date 235,630 Switzerland 1945

